This is a randomized, double-blind, placebo-controlled, parallel-group, multicenter clinical study to investigates the efficacy of fezolinetant in men undergoing ADT for prostate cancer in alleviating Vasomotor syndromes.

Participants will be randomized in a 1:1 manner to receive fezolinetant 45 mg or placebo orally once daily for 12 weeks in total, with the primary and secondary outcomes being assessed at week 4, 8 and 12 with standardized questionnaires, symptom diaries, blood taking, and clinical history taking in the clinic setting.

Inclusion Criteria:

1. Patients aged at least 18 years old on the index date
2. Histologically confirmed prostatic adenocarcinoma with localised or metastatic disease
3. Karnofsky index score of 70% or more
4. Started on androgen deprivation therapy (both medical or surgical), for at least 3 months at baseline
5. Baseline daily hot flush score ≥4

Exclusion Criteria:

1. Patients treated with drugs related to the study medications or with potential effect for vasomotor symptoms, including selective serotonin-re-uptake inhibitors, steroid hormones, clonidine, gabapentin, veralipride, or β-alanine

2. Concomitant use of CYP1A2 inhibitors, e.g. fluoroquinolone, fluovoxamine, cimetidine, propranolol, verapamil, acyclovir, allopurinol, theophylline, etc.

3. Active liver disease including:

   - cirrhosis - liver failure - jaundice - elevated total or direct bilirubin - abnormal ALT / AST - abnormal INR

4. Severe (eGFR 15 to less than 30 mL/min/1.73 m2) renal impairment or end-stage renal disease (eGFR less than 15 mL/min/1.73 m2)